A trio of techniques referred to as single-cell RNA-seq, which allows you to track development of organisms and organs in stunning detail, cell by cell and through time, is Science magazine’s Breakthrough of the Year. This year alone, papers detailed how a flatworm, a fish, a frog, and other organisms begin to make organs and appendages. And groups around the world are applying the techniques to study how human cells mature over a lifetime, how tissues regenerate, and how cells change in diseases. That technical trifecta “will transform the next decade of research,” says Nikolaus Rajewsky, a systems biologist at the Max Delbrück Center for Molecular Medicine in Berlin

Could the switch to a different pertussis vaccine be responsible for the rise in pertussis cases in the US? That’s the theory posed by University of Georgia professor Pejman Rohani, who published a study that used mathematical models to show that vaccine-based immunity to pertussis wanes more slowly than previously thought, regardless of whether the vaccinations are whole-cell or acellular type. In other words, the vaccines are fairly durable, and don’t appear responsible for the rise in cases. Rohani theorized that a vaccine containing whole Bordatella pertussis cells to an acellular version with pertussis antigens might be the reason why whooping cough is on the rise. But the study has since provoked a heated response from researchers, who published a commentary this week in Science Translational Medicine, taking issue with some of Rohani’s methodology.

Dr. Francis Collins, the Director of the US National Institutes of Health called a recent experiment in China to alter the genes of twin girls in utero to make them resistant to HIV a drastic, regrettable step” and an “epic scientific misadventure.” Dr. Collins said a modified Recombinant DNA Advisory Committee that will include scientists, bioethicists and members of the public may be able to provide “an opportunity to have a broader U.S. debate about topics that seem to need attention.”